Is there any disadvantage to using smoke adaptive domain?
I think the only reason to have it off by default is compatibility, it was a feature added to the existing smoke simulator.


  Added a new "Adaptive Domain" setting for smoke domains: Domain resolution and size adapts to only cover areas where smoke is, so that as small domain as possible has to be calculated at a time.


To enable it when opening an old file would cause a zero sized domain breaking the existing smoke simulation cache, or at the least force existing smoke caches to need re-baking. Leaving it off allows the user to re-bake only when they decide to.